Can tap

ABSTRACT

Disclosed are can taps for dispensing fluids from containers. The can tap has a housing with a housing net and a housing outlet, and a pin and a tap outlet. The pin has a flow portion in fluid communication with the housing inlet and housing outlet. The flow portion of the pin may be a hollow shaft. The pin has a blunt depressor capable of operating a valve on the container. The can tap may have a gasket comprising a material having a hardness that prevents deformation of the container.

BACKGROUND INFORMATION

1. Field of the Disclosure

This invention relates to can taps for use with containers for dispensing materials. More specifically, this invention relates to can taps for dispensing refrigerants from pressurized containers.

2. Description of the Related Art

Chlorofluorocarbon (CFC), hydrochlorofluorocarbon (HCFC), hydrofluorocarbon (HFC), and hydrofluoroolefin (HFO) compounds have been used extensively as refrigerants, as well as propellants and cleaning solvents. In response to global warming and ozone depletion concerns, new environmental pressures are continuously being exerted on refrigerant service technicians. Refrigeration and air-conditioning (a/c) systems commonly lose refrigerants due to system fatigue, servicing, and/or normal system leakage. Therefore, refrigeration and a/c systems need to be re-charged by adding refrigerant. In the automotive aftermarket, it is very common to recharge a/c systems with small (typically 12 oz. or 1 kg), pressurized refrigerant containers. Small pressurized containers are often used in the mobile aftermarket because of their portability and ability to be taken to the vehicle and re-charge the vehicle, even by do-it-yourself mechanics.

Small aftermarket refrigerant containers are typically provided as single use type containers. These containers normally have a thin metal seal that is destroyed in liberating the refrigerant. A can tap having a needle-shaped pin (which may be referred to as a “piercing tap”) pierces the thin metal seal and allows the contents to be dispensed. An example of such a piercing tap for use with such a can is shown in FIG. 6. Piercing tap 600 has pin 620 having needle-shaped tip 626 that pierces the metal seal of a can. An example of a can with a thin metal seal that can be pierced with a piercing tap is shown in FIG. 7.

The cans and can taps presently on the market have several disadvantages. Due to the thin metal seal on the can which must be pierced and ultimately destroyed to dispense the contents, the can cannot be resealed. Therefore, the cans can only be used once before they are discarded. If all of the contents are not used, the excess refrigerant is wasted. Not only does the excess refrigerant represent lost money, but the excess refrigerant is generally released into the atmosphere, which may have environmental implications.

Another issue often encountered with the piercing-type can taps (piercing taps) is inconsistent and/or stopped flow. If the needle-shaped pin is inserted too far into the can, the needle pin will block the flow of the contents out of the can. If the pin is not inserted far enough, the hole in the metal seal may be small and restrict the flow of material out of the can. In typical use, the pin must be inserted and then drawn completely out to achieve optimum flow. However, when technicians actuate the can tap, for example by turning a handle, and begin to remove the pin out of the can, the refrigerant normally starts to flow, so the technician may not fully dis-engage the pin. Finding the best flow or “sweet spot” requires practice to Cans that are self-sealing (i.e., have a seal that is capable of resealing itself) have recently been introduced in the automotive aftermarket. There are two versions of self-sealing cans. These include external spring-actuated and internal spring-actuated plug type self-sealing cans (which may be referred to as external plug can(s) and internal plug can(s), respectively, singular and plural).

The external plug can is well known and there are many taps and/or tap assemblies that are used to liberate product within an external plug can. An example of an external plug can is shown in FIG. 8.

The internal spring-actuated plug type self-sealing can is a newer design. An example of an internal plug can is shown in FIG. 9. At this time, there are no can taps that are specifically designed to work with the new internal plug cans. The seal on these cans have a spring-actuated plug that remains in a sealed position until the plug is depressed. The internal plug can has several advantages over the external plug can. The internal plug design is more robust and may be less prone to damage as the plug portion is contained within can and not external to can. The internal plug can design may also have generally higher flow rate versus the external plug can.

Currently available piercing can taps can be used to release the contents of an internal plug can, but have several drawbacks. First, the needle-shaped pin may damage the plug and/or the seal and may destroy the can's ability to release refrigerant. Second, piercing can taps also provide an inconsistent flow rate similar to the previous can designs. Third, depending on the material of construction of the needle-shaped pin, some pins cannot even sufficiently depress a spring-actuated plug to liberate refrigerant.

It is therefore desirable to develop a system that may overcome one or more of the disadvantages of the currently available products.

It may be desirable to provide a robust can and tap system that is capable of being resealed. Having a robust resealable can and tap system may allow for less material being wasted by allowing the entire contents of the can to be used for the intended purpose. Less waste may also lead to lower costs and less environmental impact.

It may also be desirable to provide a system that is easier to use and/or may yield more consistent results. For example, it may be desirable to provide a system that provides a high and/or consistent flow rate without the need to find the “sweet spot” of the pin.

SUMMARY

In at least one embodiment of the present disclosure, a can tap comprises:

-   -   a housing having a body, a lower end having an inlet, an upper         end having an outlet, a throat between the lower end and the         upper end;     -   a pin located within the housing having an upper end secured to         the housing body, a lower end having a blunt depressor suitable         for contact with a can having a top in which is positioned a         valve, wherein the blunt depressor is capable of operating the         valve of the can, and a flow portion between the upper end and         the lower end of the pin located within the housing throat         wherein the flow portion is in fluid communication with the         housing inlet and the housing outlet; and     -   a tap outlet in fluid communication with housing outlet at the         upper end of the housing.

In accordance with at least one embodiment of the present disclosure, a can tap comprises:

-   -   a housing having a body, a lower end having an inlet, an upper         end having an outlet, a throat between the lower end and the         upper end;     -   a pin located within the housing having an upper end secured to         the housing body, a lower end having a blunt depressor suitable         for contact with a can having a top in which is positioned a         valve, wherein the blunt depressor is capable of operating the         valve of the can, and a flow portion between the upper end and         the lower end of the pin located within the housing throat         wherein the flow portion is in fluid communication with the         housing inlet and the housing outlet;     -   a tap outlet in fluid communication with housing outlet at the         upper end of the housing; and     -   a gasket positioned adjacent to the housing at or near the         housing inlet,         wherein the gasket comprises a material having a hardness         ranging from about 70 durometers to about 100 durometers.

The foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as defined in the appended claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a partial cutaway view of a can tap as disclosed herein.

FIG. 2 shows a partial cutaway view of a can tap in a closed state affixed to a can in accordance with an embodiment of the present disclosure.

FIG. 3 shows a partial cutaway view of a can tap in an open state affixed to a can according to an embodiment of the present disclosure.

FIG. 4 shows a cutaway view of a can tap pin according to an embodiment of the present disclosure.

FIG. 5 shows a cutaway view of a can tap pin in accordance with an embodiment of the present disclosure.

FIG. 6 shows a partial cutaway view of an existing can tap of the prior art.

FIG. 7 shows a can having a metal seal of the prior art.

FIG. 8 shows an external spring-actuated plug self-sealing can of the prior art.

FIG. 9 shows an internal spring-actuated plug self-sealing can of the prior art.

DETAILED DESCRIPTION

Before addressing details of embodiments described below, some terms are defined or clarified.

As used herein, the terms “can,” “container,” “vessel,” “bottle,” and variations thereof, are used interchangeably to describe an item used to hold a fluid. In at least some embodiments, the fluid contents may be pressurized. For use with the can tap disclosed herein, the can has a top in which a valve is positioned, with the can capable of being affixed to a suitable can tap. The valve may be a self-sealing valve and capable of having a closed or sealed position and an open position.

As used herein, the terms “tap” or “can tap” refers to a mechanical device capable of opening a container and dispensing the contents therein therefrom.

As used herein, the term “pin” refers to the portion of the tap that creates the opening in the container through which the contents may flow from the container through the tap. The term “depressor” refers to the portion of the pin that presses against the seal of the can when the tap is in use. The phrase “capable of operating a valve of a can” means that when the tap is affixed to a can, the depressor, when actuated, is capable of opening and closing a valve by actuating (moving) the pin, for example, turning a handle, so that upon sufficient descent of the pin, the valve changes from a closed position to an open position. The closed position is the position where fluid is not being dispensed, and the open position is the position where fluids may be dispensed.

As used herein, the term “blunt” refers to a surface that is devoid of a sharp point, wherein a sharp point is one defined as having an angle less than 90 degrees.

In the FIGURES, identical features are identified using the same number and similar features may be identified with similar numbers.

In accordance with at least one embodiment of the present disclosure, a can tap comprises a housing, a pin having a depressor, and a gasket, wherein the gasket comprises an elastic material having a hardness that minimizes deformation of a can.

In at least one embodiment, the pin has a flow portion that allows fluid to flow between the housing and the pin.

In at least one embodiment, the pin shaft and the flow portion are both cylindrical. The diameter of the flow portion may be smaller than the diameter of the pin shaft.

According to at least one embodiment of the present disclosure, a can tap may comprise a housing and a pin, wherein the pin comprises a flow portion and a blunt depressor at the end of the pin. The housing has a lower end having an inlet and an upper end having an outlet. The flow portion of the pin is in fluid communication with the housing inlet and the housing outlet when in an open position. The depressor may he capable of operating a valve of a can.

In an embodiment of the present disclosure, the can tap can be affixed to and detached from a can at least about 5 times without deforming the can. In certain embodiments, the can tap can be attached and detached from a can more than about 5 times without deforming the can, for example, more than about 10 times.

In an embodiment of the present disclosure, the can tap is used with a can containing a fluid and the can tap is capable of delivering a constant flow rate of fluid of at least about 2.0 g/sec when the can has a starting pressure of 662 kPa (96 psia). In another embodiment, the can tap can deliver a constant flow rate of fluid of at least about 3.0 g/sec or at least about 5.0 g/sec when the can has a starting pressure of 662 kPa (96 psia).

In at least one embodiment, the flow portion of the pin is or has a hollow shaft having one or more openings, for example, openings along a side of the pin at the lower end of the pin adjacent to or near the depressor, in fluid communication with the housing inlet and housing outlet, to allow fluid to pass into and out of the hollow shaft.

The hollow shaft may have one or more openings along the shaft at a location remote from the depressor which may, for example, be proximal to a housing outlet, to allow fluid flow into and out of the pin hollow shaft to the housing and housing outlet and subsequently through the tap outlet.

The pin may have or terminate in a solid depressor that may contact a plug of a can seal. The seal/plug may seal a valve positioned in the can to prevent fluid from escaping a sealed can.

In embodiments where the pin has a hollow shaft, the pin may terminate in an open depressor such that the depressor is ring-shaped and fluid flows through the center of the depressor into the hollow shaft, which is in fluid communication with the housing inlet.

The pin, that is, for this embodiment, the hollow pin shaft of the pin, terminates in an open depressor, having a ring-shaped cross-section that forms the opening of the pin in fluid communication with the housing inlet and wherein an opening remote from the depressor is in fluid communication with the housing outlet.

In one embodiment, the can tap has a pin which terminates in a solid depressor and the pin is in fluid communication with the housing inlet through one or more openings in the pin located in the hollow shaft adjacent to the depressor positioned on a side of the pin, and wherein an opening in the flow portion remote from the depressor is in fluid communication with the housing outlet.

As one of ordinary skill in the art would recognize, the flow portion of the pin may have any geometry that allows fluid to flow between the can and the tap outlet. One of ordinary skill in the art will also recognize that the geometry may be designed to provide a desired flow rate. For example, when the flow portion of the pin is a hollow shaft, a larger flow portion may provide for a greater flow rate, or a smaller flow portion may be desirable to result in a lower flow rate, while dependent on other factors, such as, for example, the relative dimensions of the housing throat.

Similarly, one of ordinary skill in the art would also recognize that the geometry of the flow portion may be designed such that it promotes a particular fluid behavior, such as through the use of baffles or projections that cause greater mixing of the fluid through more turbulent flow.

According to the present disclosure, the depressor has a shape such that it may open a can (e.g., open a self-sealing valve on a can to thereby open a can). The depressor may be designed to minimize and/or prevent damage to the can or valve. For example, the depressor may have a relatively flat portion that contacts the valve to evenly distribute pressure. As one of ordinary skill in the art will recognize, the depressor should be designed such that it opens the can, that is opens the valve, such as a self-sealing valve, while also allowing fluid to exit from the can.

The depressor of the present disclosure may have a blunt surface that contacts the valve of the can. The blunt surface may be flat, curved, faceted, or dully pointed (i.e., having an angle at the tip of greater than 90 degrees). The depressor may have curved or straight sides. The depressor may also have chamfered or rounded edges.

In at least one embodiment, the depressor may have a bulbous shape.

In accordance with at least one embodiment of the present disclosure, the pin may further have a structure positioned along the flow portion of the pin to limit the distance the pin may descend when the pin is engaged, that is, a pin limiter. The tap housing may have a stop that is engaged by the pin limiter. For example, the pin limiter may have shoulders that engage the stop. The stop may be positioned along the housing throat at or near the housing inlet. The stop may be, for example, an annular protrusion that projects outward from the housing at or near the housing inlet. A pin limiter having at least one shoulder and the stop may be sized such that at least one shoulder contacts the stop to limit the distance the pin can descend. The pin limiter may be positioned to provide an optimum opening between the pin and the housing.

The tap of the present disclosure may also comprise a gasket wherein the gasket is positioned adjacent to the housing or at or near the housing inlet, and is further positioned so as to be capable of contacting a can when the tap is affixed to a can. The gasket may provide a seal between the can and the tap. Additionally, the gasket may be used to minimize or prevent deformation of the can when the tap is placed on the can.

The gasket may comprise an elastic material (e.g., elastomer) that may cushion the top of the can. A material that is too soft may compress too easily and offer little protection to the can. A material that is too hard will not compress enough and will similar afford little protection to the can. The gasket may comprise a material that at least partially but not completely compresses when the can tap is placed on the can. Compression may be, for example, at least about 1%, 5%, 10%, 20%, 30%, or 50%, or more, but is less than 100%, for example, compression may be less than about 90%, 75%, 60%.

Examples of materials that may be used for the gasket may include ABS, acetal, epoxy, fluorocarbons, PTFE, ETFE, PVDF, ionomer, Polyamide 6/6 Nylon, polyarylate, polycarbonate, polyester, PBT, PET, polyetherimide, polyethylene, polyphenylene oxide, polyphenylene sulfide, polypropylene, polystyrene, polysulfone, polyvinyl chloride, Buna N, Hypalon 48, and Thiokol FA.

The gasket may comprise a material having a hardness ranging from about 70 durometers to about 100 durometers. In at least one embodiment, the gasket comprises a material having a hardness ranging from about 80 durometers to about 90 durometers. The gasket may be selected from a material having a hardness that at least partially compresses, but does not fully compress, when the tap is mated to the can.

The size of the gasket may also be adjusted based on the material used so that the tap does not deform the can when the tap is attached to the can.

The tap may comprise any known material that is able to withstand the pressure of the can and that is resistant to the fluid contained within the can. Materials may include, for example, stainless steel, galvanized steel, aluminum, brass, bronze, plastic, etc. Pressures within the cans may be at least 662 kPa (96 psia), such as at least 689 kPa (100 psia), at least 758 kPa (110 psia), at least 827 kPa (120 psia), or higher. In at least one embodiment, the material comprising the tap should be strong enough to withstand such pressures up to at least 1.38 MPa (200 psia).

An exemplary can tap is shown in FIG. 1. In FIG. 1 and in the subsequent figures, the housing is shown in a cutaway view to expose the pin contained within the housing. Can tap 100 comprises housing 110, gasket 114, pin 120, and tap outlet 130. Housing 100 has a housing body 111 and a nut 112 that secures pin 120 to housing body 111. Housing 110 further has a throat 113, which is in fluid communication with housing outlet 116. Threads 115 are capable of matingly engaging a can (not shown), which can has threads that conform to threads of gasket 114.

Pin 120 has handle 121 that can be turned to raise or lower pin shaft 122, which engages housing 110 through threads 123. A fluid-tight engagement between housing 110 and pin 120 is maintained through two washers 128 and o-ring 127 mounted on shaft 122. Pin 120 further has flow portion 125 which is a hollow portion of shaft 122. Pin 120 terminates in depressor 126.

Openings 131 are located in shaft 122 adjacent to depressor 126 to allow fluid to enter into shaft 122. Fluid can then exit through opening 132 of shaft 122, which is remote from depressor 126 and in fluid communication with housing outlet 116.

Can tap 100 comprises tap outlet 130 that can accommodate a hose or other connector through threaded portion 134 to carry fluid from a can.

FIG. 2 shows can tap 100 of FIG. 1 affixed to can 240 and engaged with self-sealing valve 250 of can 240. Self-sealing valve 250 is shown in the closed or sealed position, i.e., valve 250 has not been actuated by tap 100. Can top 241 has threaded portion 242 that engages threads 115 of housing 110. Top 243 of can 240 has upraised crown 244 that has an opening through which depressor 126 of pin 120 can pass. O-ring 251 seals the top of valve 250 and plug 254 presses against o-ring 251 with the aid of spring 256 to prevent fluid from escaping can 240 when not engaged by can tap 100. In the example shown in FIG. 2, plug 254 has stop 255 that is a raised annular projection that contacts o-ring 251. Valve body 252 has openings 253 through which fluid can pass when plug 254 is depressed.

Handle 121, pin shaft 122, tap outlet 130, openings 131 and opening 132 are the same as discussed for FIG. 1.

FIG. 3 shows can tap 100 of FIGS. 1 and 2, but in contrast to FIG. 2, self-sealing valve 250 is shown in the open position wherein handle 121 of pin 120 has been turned to cause pin 120 to descend. Depressor 126 has engaged and depressed plug 254 by compressing spring 256. Depression of plug 254 disengages stop 255 from o-ring 251, allowing fluid to pass from can 240 through valve 250 and into tap 100. Flow portion 125 of pin 120 allows fluid to enter throat 113 of housing 110, and fluid then exits through tap outlet 130.

Housing outlet 116, openings 131 of pin shaft 122, opening 132 of pin shaft 122, valve body 252, openings 253 in valve body 252, and spring 256 are the same as discussed for FIGS. 1 and/or 2.

FIGS. 4 and 5 show alternative embodiments of the pin in accordance with the present disclosure. FIG. 4 shows a cutaway view of pin 420 having hollow flow portion 425 in shaft 422 that terminates in solid depressor 426. Openings 431 are located in hollow shaft 422 adjacent to depressor 426 to allow fluid to enter hollow flow portion 425. Fluid exits through opening 432, which is remote from depressor 426 and in fluid communication with the housing outlet (not shown).

FIG. 5 shows a cutaway view of pin 520 having hollow flow portion 525 in shaft 522 that terminates in an open depressor 526, which has a ring-shaped cross-section. Fluid enters the hollow flow portion 525 through depressor 526 and exit through opening 532, which is remote from depressor 526 and in fluid communication with the housing outlet (not shown).

One of ordinary skill in the art will recognize that the geometry of the flow portion may comprise any known geometry and is not limited to cylindrical shapes, as depicted in the drawings. Other shapes may be used depending on the desired flow rate of the fluid, the geometry of the tap housing and/or the valve, the machinery and/or method used to fabricate the pin, etc.

In accordance with various embodiments of the present disclosure, the depressor may have any number of shapes. In at least one embodiment, the depressor may be shaped such that it avoids damaging the top of the can or the valve. For example, a depressor may be shaped such that it does not contact an upraised crown on a can top, such as, for example, as shown in FIG. 2. Further, the depressor may be shaped such that it clears an o-ring that seals the top of a valve without damaging the o-ring when the depressor descends through the valve or when the depressor ascends through the valve on removal. Damage to the top of a can or valve (e.g., the o-ring) may lead to premature failure of the valve and cause the can to leak or to prevent the tap from opening the valve.

FIGS. 6-9 are illustrative of prior art and are described hereinabove.

Many aspects and embodiments have been described above and are merely exemplary and not limiting. After reading this specification, skilled artisans appreciate that other aspects and embodiments are possible without departing from the scope of the invention.

Other features and benefits of any one or more of the embodiments will be apparent from the preceding detailed description, and from the claims.

Many aspects and embodiments have been described above and are merely exemplary and not limiting. After reading this specification, skilled artisans appreciate that other aspects and embodiments are possible without departing from the scope of the invention.

Other features and benefits of any one or more of the embodiments will be apparent from the preceding detailed description, and from the claims.

Note that not all of the activities described above in the general description are required, that a portion of a specific activity may not be required, and that one or more further activities may be performed in addition to those described. Still further, the order in which activities are listed are not necessarily the order in which they are performed.

In the foregoing specification, the concepts have been described with reference to specific embodiments. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of invention.

Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any feature(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature of any or all the claims.

It is to be appreciated that certain features are, for clarity, described herein in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any subcombination. Further, reference to values stated in ranges include each and every value within that range. 

1. A can tap comprising: a housing having a body, a lower end having an inlet, an upper end having an outlet, a throat between the lower end and the upper end; a pin located within the housing having an upper end secured to the housing body, a lower end having a blunt depressor suitable for contact with a can having a top in which is positioned a valve, wherein the blunt depressor is capable of operating the valve of the can, and a flow portion between the upper end and the lower end of the pin located within the housing throat wherein the flow portion is in fluid communication with the housing inlet and the housing outlet; a gasket positioned adjacent to the housing at or near the housing inlet, and is further positioned so as to be capable of contacting a can when the tap is affixed to a can, wherein the gasket comprises an elastic material that cushions the top of the can; and a tap outlet in fluid communication with housing outlet at the upper end of the housing.
 2. The can tap of claim 1, wherein the flow portion of the pin is a hollow shaft wherein the hollow shaft has one or more openings in fluid communication with the housing inlet and the housing outlet.
 3. The can tap of claim 1, wherein the hollow shaft terminates in an open depressor, having a ring-shaped cross-section that forms the opening of the pin in fluid communication with the housing inlet and wherein at least one of the one or more openings is in fluid communication with the housing outlet.
 4. The can tap of claim 2, the pin terminates in a solid depressor and at least one of the one or more openings in the hollow shaft of the pin is positioned along a side of the pin at the lower end of the pin adjacent to or near the depressor, in fluid communication with the housing inlet, and wherein an opening in the flow portion remote from the depressor is in fluid communication with the housing outlet.
 5. The can tap of claim 1, wherein the pin has a pin limiter positioned along the flow portion of the pin for limiting the distance the pin may descend when the pin is engaged.
 6. The can tap of claim 5, wherein the pin limiter is at least one shoulder and the housing further comprises a stop positioned along the housing throat at or near the housing inlet wherein the at least one shoulder and the stop are sized such that the at least one shoulder contacts the stop to limit the distance the pin can descend when the pin is engaged. 7-8. (canceled)
 9. The can tap of claim 1, wherein the gasket has a hardness ranging from about 70 durometers to about 100 durometers.
 10. The can tap of claim 9, wherein the gasket has a hardness ranging from about 80 durometers to about 90 durometers.
 11. The can tap of claim 7, wherein the gasket is sized such that it at least partially but not completely compresses when the can tap is attached to a can.
 12. The can tap of claim 1, wherein the can tap can be attached and detached from a can at least about 5 times without deforming the can.
 13. The can tap of claim 1, wherein the can tap is capable of delivering a constant flow rate of at least 2.0 g/sec when the can has a starting pressure of 662 kPa (96 psia).
 14. The can tap of claim 1, wherein the depressor has a blunt surface for contacting with a valve of a can.
 15. The can tap of claim 1, wherein the blunt surface of the depressor is flat, curved, faceted, or dully pointed. 16-17. (canceled)
 18. The can tap of claim 14 or 15 wherein the depressor has straight sides.
 19. The can tap of claim 14 or 15 wherein the depressor has curved sides. 20-26. (canceled)
 27. The can tap of claim 11 wherein the elastic material compression is at least about 1% and less than 100%.
 28. The can tap of claim 11 wherein the elastic material compression is at least about 10%.
 29. The can tap of claim 11 wherein the elastic material compression is less than about 90%.
 30. The can tap of claim 11 wherein the elastic material compression is at least about 20%.
 31. The can tap of claim 11 wherein the elastic material compression is less than about 75%.
 32. The can tap of claim 11 wherein the elastic material compression is at least about 50%.
 33. The can tap of claim 11 wherein the elastic material compression is less than about 60%. 